[WIP] Chore: Remove unused parameters and definitions from main.parameters.json

[Copilot]

• Analyze current state of infra/main.parameters.json and infra/main.waf.parameters.json
• Review quota validation scripts to confirm expected schema and value types
• Fix aiModelDeployments in both parameter files to use concrete defaults (not ${VAR=default} placeholders)
• Verify sku.capacity is a number (integer 150), not a string
• Run code review (no issues found)
• Run security check (no issues found)

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